Preparation:Combine first 8 ingredients in a small bowl, stirring well. Rinse and pat dry lamb. Place lamb in a zip lock bag or a shallow, covered dish. Pour the marinade mixture evenly over both sides of lamb. Flip a few times to coat meat and refrigerate for 4-6 hours, flipping occasionally if you have the chance.Prepare grill by coating with cooking spray. Turn on grill to medium and let heat. Sear lamb on each side. Turn down the grill and cook for 2-4 minutes on each side or until desired degree of doneness. Garnish with mint sprigs. Serve immediately.